Deformation dynamics in pre-twinned Mg-3Al-1Zn alloy: A synchrotron X-ray study

• Published in: Materials letters Vol. 292; p. 129626
• Main Authors: Li, Z.L., Gong, X.H., Li, S.Y., Zhang, Y.Y., Chen, S., Xie, H.L., Luo, S.N., Zhang, N.B., Lu, L.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-06-2021; Elsevier BV
• Subjects: Deformation; Deformation twinning; Hardening rate; Localization; Magnesium base alloys; Materials science; Metals and alloys; Pre-twinning; Strain hardening; Strain localization; Stress-strain curves; Synchrotron radiation; Synchrotrons; Twinning; X-ray DIC; X-ray techniques; XRD; Deformation twinning; Metals and alloys; X-ray DIC; XRD; X-ray techniques; Pre-twinning
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2021.129626

•Deformation dynamics of Mg alloy is investigated with in situ X-ray multiscale diagnostics.•Deformation induced by twinning has a slowing effect on strain localization.•Strain localization in the as-received and pre-twinned samples exhibit differences.
We investigate the deformation dynamics in pre-twinned Mg-3Al-1Zn alloy under uniaxial compression based on in situ synchrotron X-ray diagnostics. Stress-strain curves, strain field mapping and X-ray diffraction are achieved simultaneously. The same measurements are conducted on the as-received Mg alloy for comparison. Massive {101¯2}–{101¯2} double twinning is observed in preexisting twins of the pre-twinned specimen, and abundant {101¯2} extension twins are activated in the as-received specimen. The {101¯2} extension twinning in the as-received specimen can rapidly boost strain hardening rate by slowing down the process of strain localization. The {101¯2}–{101¯2} double twinning does not lead to significant reduction in the rate of strain localization, and thus the corresponding increase in strain hardening rate is modest.